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Food & Drink Mercury rising

Last week, Michael Bender, the head of the Vermont-based Mercury Policy Project, was trekking toward the peak of Hunger Mountain to take in the breathtaking fall leaves. Closer to sea level, Bender is concerned about a public hungry for facts about their fish consumption. While doctors tout the health benefits of eating fish because of its heart-healthy omega-3 fatty acids, two federal agencies and the American Medical Association also caution against consuming too much of certain species because of their high mercury content.

To eat those luscious, succulent tuna steaks, or not to eat those luscious, succulent tuna steaks - that is the question.

The answer: Eat them, but infrequently.

A recent study issued by the Mercury Policy Project shows that swordfish sold in groceries nationwide tested above the federal limit of 1 part per million for methylmercury. Mercury is a natural, but toxic, element generated by degassing from the earth's crust and oceans, but the uptick in the global load is due largely to the increase worldwide of emissions from coal-fired power plants and other fossil fuels. Mercury emitted from smokestacks travels on the wind, mixes with moisture from clouds, and returns to earth in the more toxic form of methylmercury.

Of 24 stores where MPP took samples, half, including Shaw's, Albertson's, Genuardi's, Whole Foods, and Kroger locations, were selling fish that exceeded the action level established by the Federal Drug Administration. A Whole Foods in Austin stocked swordfish that tested at 1.26 ppm. While the 31 tuna samples tested lower, averaging .33 ppm, the FDA and EPA advise limiting tuna consumption as well.

The tests were conducted at the University of North Carolina Environmental Quality Laboratory in July and August.

As a result of the testing, the Mercury Policy Project has asked grocers to post advisories in their seafood sections informing consumers of the risks of eating fish that tend to accumulate mercury in their bodies. The American Medical Association has issued a similar advisory. The larger and more predatory species eat smaller fish and aquatic life, adding to their mercury burden. Fish also absorb mercury from water.

Freshwater fish that live in areas where the mercury levels are elevated can also absorb more of the toxin.

"Chains have a responsibility to get the message out to the public," Bender said. "We want to encourage people to eat fish by reducing or eliminating consumer confusion. And we're most concerned about pregnant women and developing fetuses."

Read before eating

Nearly all species of fish have methylmercury in them, although some species accumulate the element more than others, depending on their habitat, food sources, and size. FDA guidelines have approved the consumption of most fish two to three times a week, although they recommend that pregnant women, nursing mothers, and children should avoid eating:

King mackerel Tuna steaks and albacore Shark Swordfish Tilefish

For other fish-eaters, the FDA/EPA advisory suggests limiting consumption of these species to no more than four 6-ounce servings per month.

A 2002 National Academy of Sciences study suggested that fetuses could suffer detrimental developmental effects if their mothers ate large quantities of fish contaminated with high levels of methylmercury.

The FDA advises pregnant women and women of childbearing age who may become pregnant not to eat fish with high levels of methylmercury more than once a month. Other fish eaters can consume one serving a week. For fish with lower levels of methylmercury, such as shrimp, salmon, pollock, canned light tuna, and catfish, consumption should be limited to two servings a week.

Symptoms of methylmercury poisoning in children and adults include stumbling gait, numbness and tingling sensations, fatigue, tunnel vision, hearing loss, tremors, headache, and inability to concentrate. Incidents of acute poisonings have been recorded, including an episode in the 1960s in which 111 people died or became seriously ill after eating highly contaminated fish (often daily over extended periods) from waters that were severely polluted with mercury from local industrial discharge.

The Food Marketing Institute, a lobbying group that represents the grocery industry, supports point-of-sale warnings, stating that their store members have either posted warnings or plan to do so soon.

Wild Oats, a natural-food grocer with 100 stores in 20 states, posts advisories in its seafood sections, as does Whole Foods in San Antonio, which offers free literature about methylmercury in seafood, including fish consumption advisories and government information about which species are safer to eat and in what quantities.

In an e-mail correspondence, Whole Foods spokesperson Ashley Hawkins said the chain is educating shoppers about varying the types of fish to eat through in-store brochures and its website. "It is important to note that levels can vary greatly fish by fish and that it is not feasible to test fresh product for methylmercury levels as there is a two-to-three-day minimum `wait for test results`. Testing one fish for levels of methylmercury is not representative of fish that come in on a consistent basis."

H-E-B did not return calls or e-mails to the Current, but when the Current visited several stores, including Central Market, no signs or literature about methylmercury and seafood were visible.

The $60 billion-a-year seafood industry is taking a hit from the methylmercury contamination. Since March 2004, when the FDA issued its advisory, canned tuna sales have decreased 10 percent, costing the industry $150 million.

In addition to public-relations campaigns to address consumer concerns, the seafood industry is lobbying Congress to eliminate mercury in medical and industrial uses. In 2003, a bill passed the U.S. House that would have banned the sale of mercury in thermometers, but failed in the Senate. However, a significant source of mercury emissions - coal-fired power plants - are as yet unregulated; the Bush administration has stalled efforts to require utilities to reduce mercury emissions, instead favoring a program that would allow light polluters to sell pollution credits to heavy polluters. Critics say this program will concentrate pollution in certain regions while failing to reduce the overall load.

"We've known about mercury in fish for 20 or 30 years," Bender said. "A lot of countries are putting out fish consumption advisories; the United Nations is weighing in. It's not as if this is some obscure phenomenon. It's recognized as a global problem." •